Pedelec sensor - missing magnets

[Mussels]

This morning on the way in to work my pedelec started acting up in a similar way to what's described here (lumpy, irratic, pulsating power).

Did anyone ever manage to get a solution?

Cheers

Steve

I had a problem when my chain came off and the pedelec disc was knocked at an angle, once straightened the pedelec started working again. Not quite the symptoms you had but worth a look.

 

[torrent99]

I had a problem when my chain came off and the pedelec disc was knocked at an angle, once straightened the pedelec started working again. Not quite the symptoms you had but worth a look.

Thanks Mussels... I did notice that the sensor was very slightly bent, so I've bent it back but haven't had chance to test it yet.

BTW are we sure the pedelec is magnet based? The disc has holes in it which suggests an optical system?
(A source for replacement magnets would appear to be Maplins if they are required)

Cheers

Steve
PS. Is that your bike parked on London Wall?

 

[Blew it]

Only 5 of the holes in the disc are occupied by magnets. The disc should be 2-3 mm away from the sensor, any closer will allow road grit to wear it away, too far away could result in intermittant sensing. The disc is held on the crank axle by plastic gripper fingers and can be moved easily to set the distance.

If the motor runs smoothly on the throttle, then it's possible water is entering the sensor as it did on mine. Tip the machine upside down and check the sealant where the cable enters the sensor. Using a hairdrier, dry the sensor thoroughly until the pedelec function returns to normal and then add extra sealant to the back of the sensor, working it well into the cable entry. Once the sealant is cured it should be fine. Bathroom sealant or fishtank sealant can be used.

If this fails to cure the problem, then I'm afraid it will need further investigation.

All the best

Bob

 

[torrent99]

Only 5 of the holes in the disc are occupied by magnets. The disc should be 2-3 mm away from the sensor, any closer will allow road grit to wear it away, too far away could result in intermittant sensing. The disc is held on the crank axle by plastic gripper fingers and can be moved easily to set the distance.

If the motor runs smoothly on the throttle, then it's possible water is entering the sensor as it did on mine. Tip the machine upside down and check the sealant where the cable enters the sensor. Using a hairdrier, dry the sensor thoroughly until the pedelec function returns to normal and then add extra sealant to the back of the sensor, working it well into the cable entry. Once the sealant is cured it should be fine. Bathroom sealant or fishtank sealant can be used.

If this fails to cure the problem, then I'm afraid it will need further investigation.

All the best

Bob

Thanks Bob & Mussels, it was indeed a slight disturbance to the alignment of the sensor and disc (probably happened during the serious man handling required to get it in and out of the bike shed!).

Cheers

Steve

 

[Mussels]

PS. Is that your bike parked on London Wall?

It could well be, that's where it sits most days. Theft problem is bad along there.